: In my new house, the whirlpool bath drain is very noisy making slurping sounds through the overflow. The plumber that installed the tub says that is normal. I think it is poor installation of the vent system. What is the answer?

Charles, If the drain makes a sound like glub glub glub, then it isn't vented to well. If you are in a city where the code is inforced I would say it is vented. There are different codes and different ways of venting.Some better than others. UPC is the best. Dale Peck LMP